1. Field of the Invention
The present invention relates to toner for electrostatic latent image development used for printers, copying machines, facsimiles and the like, and an image forming method using the same.
2. Description of Related Art
Nowadays, a method for developing an electrostatic latent image development as typified by electrophotography is widely used for methods for forming images in printers, copying machines and facsimiles.
This is because it is a high-quality finished method where high-quality images with high speed are stably given, but some problems still remain. In the toner for electrostatic latent image development (hereinafter, also simply referred to as the toner), it is desired to reduce particle sizes and uniform the particle sizes with aiming to increase image quality. Recently, polymerization toners have been actively developed as methods for manufacturing such toners with small size where a volume average particle size is about 3 to 8 μm.
The toner obtained by polymerization method is obtained by a method for making resin particles by polymerizing a radical polymerizable monomer in an aqueous vehicle and making the toner without taking step of pulverizing and subsequently classifying. As the methods for making this polymerization toner, there are the method for preparing toner in an uneven shape by associating or salting out/fusing resin particles and coloring agent particles, and the method where a radical polymerizable monomer and a coloring agent are mixed, then dispersed as liquid droplets in an aqueous vehicle to become the desired toner particle size and suspension polymerization is performed.
In these, the method for preparing the toner in an uneven shape by associating or salting out/fusing the resin particles and the coloring agent particles is the preferable method as the method for forming the toner in an uneven shape.
Whereas, in the study by the present inventors, it have been found that toner off-set sometime occurs, when the polymerization toner is used for especially a contact type heat fixing unit, if used for a long term.